Canada's oil sands emit more carbon dioxide than average crude so developers need a clearer picture of where greenhouse gas regulations are headed to find the best way to tap the giant resource, experts said.

Democrats in the US House of Representatives have negotiated a climate change bill that would give industries most of the pollution emission permits they would need, according to documents obtained on Friday.

Fifteen percent of emissions permits would be sold to polluters each year under a climate change bill moving through the US House of Representatives, according to a document circulated on Friday describing the legislation.

Oil refiners would be given 2 percent of greenhouse gas emission permits under a proposed climate change bill that Democrats in the US House of Representatives are writing, according to a document describing that legislation.

Democrats in the U.S. House of Representatives on Thursday said they were working out final details of a climate change bill, as they announced new breaks for industry that they said would also minimize the potential impact on consumers' energy bills.

"We have reached agreement on most key matters," said Representative Rick Boucher, who represents the coal-producing state of Virginia.

U.S. steel companies are not too happy with President Barack Obama these days.

Industry executives say that in the last 15 years, they have cut their carbon dioxide emissions by one-third. But now, they think the president's cap-and-trade rules, currently in Congress, would punish them for doing what they feel they have already done -- cut pollution.

Australia's government introduced carbon trade laws into parliament yesterday. But Kevin Rudd, the prime minister, faces a battle to get them passed into law and warned that he might need an early election if his reforms were blocked.

With a series of compromises on the stickiest issues behind them, the House Energy and Commerce Committee is poised to approve far-reaching legislation on energy and global warming by the end of next week. Where it goes from there remains highly uncertain.

Unless advocates of a cap-and-trade emissions scheme can design a credible and well-funded compensation mechanism to compensate the losers (including coal miners, heavy industrial workers, and their communities) carbon control policy risks becoming mired in the same controversy as trade liberalisation.

US electricity generators support compromises being reached by Democrats in the House of Representatives on proposed climate legislation, saying the changes would soften the impact on power bills.